Electrical connectors which are adapted for mounting to printing circuit boards typically have a plurality of terminals for electrically engaging respective circuit traces on the surface of the board. The electrical engagement most commonly is effected by one of two systems. First, the terminals may have pin portions projecting from the connector for insertion into plated-through holes in the board wherein conductive plating material on the inside walls of the holes make electrical connection to circuit traces on the board surface. Second, the terminals may have leg portions extending generally parallel to the board surface and into engagement with the solder traces on the board surface. In both systems, the electrical engagement commonly is effected by soldering the pin portions to the circuit traces or the plating material in the holes in the board, or the leg portions to the circuit traces on the surface of the board.
In contemporary surface mount techniques, the individual terminals of the surface mount connector are connected to reflow solder pads of the circuit traces on the surface of the board. Increasing miniaturization and complexity of integrated circuit devices necessitates that the terminals be both relatively thin and closely spaced, with the resulting fragility requiring that the connector housing, itself, also be secured to the circuit board to afford strain relief for the terminal electrical engagements. A common type of strain relief has been provided for many years by mounting pegs or "boardlocks" which project from the connector housing into mounting or locking holes in the printed circuit board. However, with the increasing miniaturization and complexity of integrated circuit devices, such boardlocks consume valuable "real estate" on the circuit board. In addition, if electronic devices are to be mounted on both opposite sides of the board, mounting pegs or boardlocks cannot project through the board to the opposite side of the board where they will interfere with other electronic devices. Consequently, it is becoming common practice to secure such connectors on the surface of a printed circuit board by using a metal retaining device having a first portion anchored to the connector housing and a second, soldering portion attached to a dummy pad on the circuit board by reflow soldering. This invention is directed to improvements in such retaining devices which, themselves, are surface mounted to the printed circuit board.